Valve manifold circuit board with serial communication and control circuit line

ABSTRACT

A fluid control system has a first series of connected circuit boards that each actuate a respective valve unit mounted to a manifold block. A first communication module has a valve driver with a plurality of outputs for actuating the valve units connected to the first series of connected circuit boards. A serial control line extends through the first series of connected circuit boards and is connected to a second driver for actuating a second series of connected circuit boards.

TECHNICAL FIELD

The field of this invention relates to a single line communication pathbetween a driver and slave device, for example a solenoid actuated fluidcontrol valve manifold assembly and a proportioning valve and moreparticularly to a multi-station circuit board for use with the manifoldassembly having a single communication and control line.

BACKGROUND OF THE DISCLOSURE

Fluid control systems for controlling flow of hydraulic or pneumaticfluid have been used in automated manufacturing equipment, productionlines and numerous industrial applications. Many of these fluid controlsystems take the form of a valve manifold that has a series of manifoldmembers assembled together. Each manifold member commonly includes amanifold valve block and a control valve mounted thereon. The controlvalve may have a solenoid that actuates the valve and has a springreturn for moving the valve when the solenoid is deactuated. Othercontrol valves use a double (or dual) solenoid valve that has a firstsolenoid when actuated that moves the valve to the on position and asecond solenoid when actuated that moves the valve to the off position.

Each manifold block houses a circuit board which has circuitry printedthereon to allow actuation of the control valve mounted to the manifoldblock. The circuit board also has circuits printed thereon to carryvoltage to other circuit boards for the other control valves mounted onother manifold blocks.

The number of circuit boards connected together are usually limited byeither the capacity of the driver in the communication module or theinherent design of the individual circuit boards. However, an expansionmodule with its own driver can be placed at the end of the first seriesof circuit boards to drive a second series of circuit boards and controlvalve thereby increasing the capacity of the valve manifold.

What is needed is a single line system between a driver and a slavedevice that provides information and control in the form of powertherebetween that can be used for smart slave devices or other slavedevices. In particular, it is desired that a circuit board passingthrough a manifold block has a serial or single communication line foreach respective control valve and/or supplementary control, programmingor parameterization. With the advent of smart slave devices, for examplesolenoid valves, proportional devices or pressure switches, it isdesirable to transfer sensing data and control signals between a driverand a slave device.

What is also needed is a single control line through the first series ofcircuit boards that controls a second driver to control at least oneproportional valve and other field devices by providing a variableoutput based on the variable input voltage.

SUMMARY OF THE DISCLOSURE

In accordance with one aspect of the invention, a driver device drives avalve manifold block for a fluid valve manifold that has a plurality offluid pathways and ports therein controlled by a slave device in theform of a valve unit operably mounted thereto. A passage passes throughthe valve manifold from a first side to a second side of the valvemanifold block. A printed circuit board that is received in the passagehas a first edge in proximity to the first side with a plurality offirst electrical connectors and a second edge in proximity to the secondside with a plurality of second mating electrical connectors to connectto respective first electrical connectors in another printed circuitboard in another valve manifold block.

The circuit board has a set of conductive valve control lines connectedto and extending between a respective set of first electricalconnections and a set of respective second mating electrical connectors.The circuit board also has at least one conductive valve control lineextending from a respective first electrical connection to a thirdconnector on the circuit board operably leading to one voltage side of avalve unit. A conductive common line is connected to the third connectoroperably connected to an opposite voltage side of the valve unit andalso connected to a respective first electrical connector and arespective second mating electrical connector. A serial communicationline has a respective first electrical connector at the first edge and arespective second mating electrical connector at the second edge forconnection to a respective serial communication line in another valvemanifold block for communicating information relating to the valve unit.

In one embodiment, the serial communication line extends to and isconnected to a low voltage side of the valve unit. Optionally, thecircuit board serves a second valve unit on the valve manifold block.The serial communication line extends to and is connected to a lowvoltage side of the second valve unit.

In one embodiment, the serial communication line is used as a detectioncircuit line to detect if the valve unit mounted to the valve manifoldblock uses a single solenoid valve unit or double solenoid valve unit.The circuit board serves a second valve unit on the valve manifoldblock. The set of conductive valve lines extend from a set of firstelectrical connectors at the first edge and extend to and shifted to astaggered relative position at a set of second mating electricalconnectors. A leg line is preferably connected from the third connectorto the detection circuit line through a diode to only allow current topass in the direction from the leg line to the detection circuit line.

According to another aspect of the invention, fluid control system has afluid valve manifold with a plurality of valve manifold blocks fastenedto each other so as to form fluid pathways extending through themanifold and a passage through each valve manifold that aligns with eachother to collectively form a continuous electrical conduit for receivinga series of connected circuit boards that actuate a respective valveunit mounted to a respective valve manifold block. Each circuit boardhas a set of conductive valve control lines connected to and extendingbetween a respective set of first electrical connectors and a respectiveset of second mating electrical connectors. A conductive common line isconnected to a third connector operably connected to one voltage side ofthe valve unit and also is connected to a respective first electricalconnector and respective second mating electrical connector forconnection to a respective conductive line in another valve manifoldblock. A serial communication line in each circuit board has arespective first electrical connector at of the first edge and arespective second mating electrical connector at the second edge forconnection to a respective serial communication line in another valvemanifold block.

At least one circuit board serves at least one double solenoid valveunit having two conductive valve lines for each double solenoid valveunit extending from the first electrical connector to a third connectorat an opposite voltage side of each double solenoid valve unit at thevalve manifold block for actuating each double solenoid valve unit. Atleast one circuit board serves at least one single solenoid valve unithaving a conductive valve line for each single solenoid valve unitextending from the first electrical connector to a third connector at anopposite voltage side of each single solenoid valve unit at therespective valve manifold block for actuating each single solenoid valveunit. The serial communication line for the at least one circuit boardserves the at least one single solenoid valve unit by extending to andconnecting to a low voltage side of each single solenoid valve unit forcommunicating information relating thereto.

Preferably, a leg line is connected from the third connector to thedetection circuit line through a diode to only allow current to passfrom the leg line to the detection circuit line.

Also, preferably, the set of conductive valve lines extend from therespective set of first electrical connectors at the first edge andextend and are shifted to a staggered relative position at the set ofsecond mating connectors.

In accordance with one aspect of the invention, a serial communicationcircuit line includes a master, e.g. a driver device, which is normallyused to energize a load through an operating circuit; e.g. a powercircuit. The master drive circuit is designed in such a way that it notonly turns the load on or off through a power circuit, but also sendsdata to the load through a single wire for reading and/or writingvarious parameters which can be used for diagnostic information or tochange the functionality of the load. The load can be in the form of asmart slave device, (e.g. “smart” solenoid valve, proportional device,pressure switch or other component that requires monitoring, control orparameterization), which has appropriate circuitry to decipher andinterpret the data sent from the master driver and can also report backinformation from the slave device to the master driver through the samesingle wire.

The single wire communication system usually in a form of a trace on theslave device board uses a bias voltage to power the electronic circuitrywithin the slave device. The master then modulates the current to thesingle wire trace in order to create voltage pulses that are greaterthan the bias potential thereby allowing the slave to identify that datais coming from the master.

The slave can only respond to a master's request or command, it cannotinitiate communication. When responding to a master's request, the slavemodulates the current to the single wire trace in order to createvoltage pulses that are less than the bias potential thereby allowingthe master to identify that data is coming back from the slave.

The handshaking routine can be comprised of data frames which has astart bit, 8 data bits and one stop bit. The complete data frame has 8bytes, an address byte, a command byte, five data bytes and one checksumbyte. The checksum byte is simply the sum of the preceding seven bytesand is used for error detection.

Addressing the slaves is required since the single wire communicationtrace is usually connected to a plurality of slave devices. Thus, it isimportant to identify which slave device is being addressed. Thisaddressing function is done on initial power-up, or is initiated by theuser when appropriate, and is achieved by the utilization of theexisting “coil output” signals which are typically used to energizesolenoid coils of conventional valves.

Upon power-up, the “coil output” signals are configured to sequentiallystrobe each coil trace with a very fast pulse, which is too fast toenergize the coil of an attached valve. A sensing circuit in the slaveis then triggered by the strobe pulse to allow that specific slave toreceive an address.

Once the first slave gets an address from the master, the strobingsequence is incremented so the next slave device can be assignedsequential addresses. The system continues this addressing routine untilall possible slave devices get a sequential address.

After all slave devices are addressed, the master can communicate toeach individual slave device without affecting any other slave devices.

For example, the driver device is a smart valve driver device uses“active high” or PNP driver ICs to drive each of 32 coils on the valvemanifold. The common for all 32 coils is 0 VDC. An isolated “switched”power is used to drive the manifold coils and is completely isolatedfrom the “unswitched” power when used to power the logic and inputsections of the manifold. Like a conventional valve driver, the smartvalve driver receives its output data from the communication module. Thevalve driver then updates the drive ICs every 2 milliseconds with theoutput data which turns the coils on or off depending on the I/O datasent from the communication module.

In accordance with another aspect of the invention, a fluid controlsystem includes a fluid valve manifold with a plurality of valvemanifold blocks fastened to each other so as to form fluid pathwaysextending through the manifold and a passage through each valve manifoldthat aligns with each other to collectively form a continuous electricalconduit for receiving a first series of connected circuit boards thateach actuate a respective valve unit mounted to each valve manifoldblock. Each circuit board has a set of conductive valve lines connectedto and extending between a respective set of first electrical connectorsand a respective set of second mating electrical connectors. A firstcommunication module with a valve driver with a plurality of outputsactuates the valve units connected to the first series of connectedcircuit boards. A conductive common line is connected to one voltageside of a respective first electrical connector and respective secondmating electrical connector for connection to a respective conductivecommon line in another valve manifold block.

A serial control line extends through the first series of connectedcircuit boards that is connected to a second driver for actuating asecond series of connected circuit boards. The serial control line isformed from a serial control line segment in each circuit board that hasa respective first electrical connector at the first edge and arespective second mating electrical connector at the second edge forconnection to a respective serial control line segment in anothercircuit board in another valve manifold block. The serial control lineis constructed to control the voltage at the plurality of outputs of thesecond driver to control the voltage input to the valve units connectedto the second series of connected circuit boards. Preferably, at leastone valve that is connected to one of the circuit boards in the secondseries of connected circuit boards is a proportional valve.

BRIEF DESCRIPTION OF THE DRAWINGS

Reference now is made to the accompanying drawings in which:

FIG. 1 is an exploded side elevational view of a fluid control system inaccordance with one embodiment of the invention;

FIG. 2 is an enlarged side elevational view of one circuit boardinstalled in a manifold block for two valve units as shown in FIG. 1;

FIG. 3 is a perspective view of a circuit board for two single solenoidvalve units in accordance with one embodiment of the invention;

FIG. 4 is a perspective view of a circuit board for two double solenoidvalve units in accordance with another embodiment of the invention;

FIG. 5 is a plan view of a first face of the circuit board for twosingle valve units as shown in FIG. 3 illustrating the circuit layout;

FIG. 6 is a plan view of a second face of the circuit board for twosingle valve units as shown in FIG. 3 illustrating the circuit layout;

FIG. 7 is a schematic end view of a first edge of the circuit board fortwo single solenoid valve units as shown in FIG. 3 illustrating theterminals' connections to respective circuits in the circuit board;

FIG. 8 is a schematic end view of a second edge of the circuit board fortwo single solenoid valve units as shown in FIG. 3 illustrating theterminals' connections to respective circuits in the circuit board;

FIG. 9 is a schematic view of the detection circuit installed on thefirst face of the circuit board for two single solenoid valve units asshown in FIG. 3;

FIG. 10 is a plan view of a first face of the circuit board for twodouble solenoid valve units as shown in FIG. 4 illustrating the circuitlayout;

FIG. 11 is a plan view of a second face of the circuit board for twodouble solenoid valve units as shown in FIG. 4 illustrating the circuitlayout;

FIG. 12 is a schematic end view of a first edge of the circuit board fortwo double solenoid valve units as shown in FIG. 4 illustrating theterminals' connections to respective circuits in the circuit board;

FIG. 13 is a schematic end view of a second edge of the circuit boardfor two double solenoid valve units as shown in FIG. 4 illustrating theterminals' connections to respective circuits in the circuit board;

FIG. 14 is a schematic view of a circuit leads connected to the fourvalves in the two solenoid double valve units for the circuit boardshown in FIG. 4;

FIG. 15 is a schematic view of an alternate embodiment in accordancewith the invention between a smart master and smart slave valve devicewith two coils; and

FIG. 16 is a schematic view of an alternate embodiment of the inventionshowing a control line extending through a first series of circuitboards to control a second series of circuit boards that can controlproportional valves.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to FIGS. 1 and 2, the fluid control system 10 is modularin nature and depending on the application has a varying number of valvemanifold blocks 12 interconnected together. Only two manifold blocks 12are shown for simplicity of the drawings. Some of the valve manifoldblocks 12 may have single solenoid valve units 13 mounted thereon andsome of the valve manifold blocks 12 may have double solenoid valveunits 14 mounted thereon. Sometimes double solenoid valve units arereferred to as dual solenoid valves. All blocks 12 are connected to acommunication module 15. The manifold block 12 has fluid supply andexhaust ports 17 therethrough that are connected through ports (notshown) that lead to the valve units 13 and 14 to control fluid flow.

Preferably, each valve manifold block 12 may accommodate two singlesolenoid valve units 13 or two double solenoid valve units 14. Eachvalve manifold block 12 has a passage 28 that receives a single circuitboard assembly 30 or a double circuit board assembly 32. Referring nowto FIGS. 3 and 4, each circuit board assembly 30 and 32 may have a board34 with a pair of stop shoulders 36 that engage appropriate shouldersand grooves in the passage 28. Each circuit board may also have a pairof flexible tab arms 37 that also similarly engage the groove in thepassage such that the circuit board can be removably installed into thepassage 28 by a snap fit.

Each circuit board 30 and 32 has pin connectors 38 and 39 mounted on arespective board 34. Each board has a first edge 40 and second edge 42with respective trace contacts 44 and 46. As shown in FIG. 3, a standardbridge connector 43 electrically connects the aligned trace contacts 44and 46 of adjacent boards 30. The single board 30 has a diode assembly48 mounted thereon. Circuit board 32 is absent this diode assembly 48 asillustrated in FIG. 4.

Referring now to FIGS. 5 through 9, the board 30 as shown in FIG. 3 willbe described in further detail. The first edge 40 may have tracecontacts 44 on both faces 52 and 54 of the board. As shown in FIGS. 7and 8 the terms labeled A or B, e.g. A1-A19 and B1-B19 as a prefix referto the positions of the contacts and conductive lines on the respectiveside 50 or 52. The terms labeled with the V as a prefix, e.g. V1, V2,etc. refer to the downstream valve number that the circuit operatescounting from the shown circuit board. The number notation, e.g. 56, 66are the conductive printed circuit lines on each board. A set ofconductive valve lines 56 labeled V3 through V31 in FIGS. 7 and 8 onboth faces 52 and 54 extend from one edge 40 to the second edge and maybe decremented one position from edge 40 to edge 42. For example, onface 50, V3 at position A5 on edge 40 drops one position to position A4on edge 42 to be connected to a V1 contact at position A4 on edge 40 ofa sequential board. On face 52, V4 at position B5 on edge 40 may dropone position to position B4 to be connected to a V2 contact at positionB4 of the sequential board. Top contacts at position A19 and B19 are notconnected to any conductive lines on the board. In this particular showncircuit board, V31 indicates that the valve manifold using that circuitboard is limited to a maximum thirty-one solenoid valves. Other layoutsfor the circuit board lines are possible to arrange for less or for moresolenoid valves.

At first edge 40, the conductive valve line 66 corresponding to positionA4 and operating the first valve V1, i.e. the valve on the presentmanifold block 12 leads to pin connector 38. Another conductive valveline 76 corresponding to position B4 and operating the second valve,i.e. the second single solenoid valve on the present manifold block 12leads to pin connector 39. The pin connectors 38 and 39 are connected tothe respective valve units 13. Each valve solenoid unit 13 is alsorespectively connected to pin connectors 38 and 39 which are connectedto legs 91 and 92 that lead to a common voltage line 86 labeled Vcomn ateach face 52 and 54. The Vcomn lines 86 at each face are connected toeach other. The lines 86 are normally connected to a 24 volt supply topower all of the valve units 12 and 13.

Conductive lines 56 and 66 corresponding to V1 and V2 also both havelegs 58 and 59 leading to a respective diode 60 and 62 in diode assembly48. Each diode has its output connected to a leg 64 as clearly shown inFIG. 9 that connects to a leg 94 that leads to a detection circuit line96 that extends from edge 40 to 42 at positions A1 and A1 at each edge.This detection line 96 as well as the common voltage line 86 labeledVcomn are not decremented but pass straight through from one edge to theother without dropping any positions. Other lines such as an auxiliarypower circuit lines 72 labeled 24 VDC at position B2 and its return line74 labeled 0 VDC at B1 as well as a protective earth line 82 labeled PEand often referred to as a ground at position A2 may also pass straightthrough without any decrementation of position. Legs 97 and 98 connectline 82 to the respective connector pins 38 and 39.

Referring now to FIGS. 10-14, the double circuit board 32 is constructedto mount two double solenoid valve units. Similar or corresponding partnumbers from the board 30 will have corresponding similar numbers. Assuch, a set of conductive valve lines 56 labeled particularly V5 throughV32 at edge 40 corresponding to position A6-A19 on face 50 and positionsB6-B19 on face 52 pass to edge 42 and are decremented two positions i.e.to positions A4-A17 on face 50 and B4-B17 on face 52 such that theyconnect to corresponding positions on a sequential board. At edge 42,contacts A19 and A18 on face 52 and B19 and B18 are not connected to anyconductive lines on the double board 32.

The board 32 has conductive valve lines 66 for V1 and V2 connected topin connector 38 and conductive valve lines 76 for V3 and V4 areconnected to pin connector 39 to power the two double solenoid valveunits 14. Similar to the single circuit board 30, the double board 32has a common voltage line 86 labeled Vcomn at each face 50 and 52 topower all the valve units, detection line 96, auxiliary power circuitlines 72 labeled 24 VDC and its return line 74 at 0 VDC, and protectiveearth line 82 PE or ground line that are not decremented. The detectionline 96 at position A1 is not connected to the connectors 38 or 39 orthe double valve units associated with this double circuit board 32.

In this valve operation, there is a sinking driver, i.e. power linewhich is supplied to along conductive power line 86 which is connectedto all solenoids. In order to actuate the valve, each line 56, 66, or 76must individually be grounded. This is usually done through an IC chipor driver at the end of the line, e.g. at the communication module 15and connected to all of the conductive lines 56, 66 and 76. When aselected line is grounded, electrical current is then able to flow fromthe common power line 86 labeled Vcomn and through the selected solenoidand to ground to actuate an individual valve V1-V32. However, it is alsoforeseen that a sourcing driver can also work, i.e. a grounding commonis connected to all solenoids and to actuate a valve, a voltage, forexample 24V is individually connected.

The detection line 96 can be used to determine if the circuit board is asingle board 30 or a double board 32. In one method, all the conductivevalve lines 56, 66, and 76 are actuated. In the shown system, thisactuation is done by grounding the valve lines V1-V32 through an ICcomponent or driver connected at one end from the first board. The powersupply line 86 Vcomn is then able to provide current through eachsolenoid and down through the individual lines V1-V32. In operation, allthe solenoid valves are actuated and the V1-V32 lines are grounded, thusthe voltage detected on the detection line 96 is 0V.

Each contact is selectively and individually deactuated, i.e. turned offin sequence by the driver IC circuit usually housed in communicationmodule 15. When the V1 line in the shown circuit board 30 is turned off,the V1 line is no longer grounded so V1 line reads 24V, in other wordsit now has the same voltage as the Vcomn line. The leg 58 which isdirectly connected to the V1 line also reads 24V and passes through thediode 60 as shown in FIG. 9 to outlet leg 94 on the circuit board whichconnects to the detection line 96. The detection line 96 then reads 24V.

The V1 line is then re-actuated, and the V2 line is deactuated.Similarly, the V2 line will then read 24V when the V2 line isdeactuated. The detection leg 94 downstream of diode 62 again reads 24V.Thus, when V1 and V2 lines both are sequentially deactuated and thedetection lines reads 24V for both deactuations, it is thus determinedthat the circuit board associated with V1 and V2 for this board is asingle solenoid circuit board 30.

On the other hand, if the four voltage lines i.e. V1-V4 of double board32 are actuated and deactuated in sequence, the detection line 96 asshown in FIG. 14 does not change from its 0V readout, because it is notconnected to any of line V1-V4 on this double board 32. Thus, when thedetection circuit line reads 0V when the fours lines V1-V4 aresequentially actuated and deactuated, it can be deduced that the circuitboard associated with these four valve lines are with a double solenoidboard 32.

The process of the driver sinking (or sourcing) the voltage charge forthis detection is very fast, so as not to change the position of thevalve. For example, a sinking pulse or strobe connected by the driver to0V can be 0.2 milliseconds. This is substantially too short tomechanically move the valve from its previous position. Furthermore,when the strobe is sent to valve status V1, none of the other valvelines V2-V32 are affected, because they did not receive this strobe.

Other logical mapping and communications can be used with this singledetection line 96 that passes through all the circuit boards 30 and 32.For example, if only one-line V2 reads 24 V when deactuated but V1remains at 0V when deactuated, it may be deduced that there is a no coilor solenoid valve in the valve unit associated with V1.

It is also foreseen that instead of or in addition to a detection line,a single serial communication line may be used in other embodiments andfor other purposes than detecting the presence of single and doublesolenoid circuit boards and the presence or absence of single or doublesolenoid valve units mounted on the valve manifold units of a fluidcontrol system. Referring now to FIG. 15, a serial communication line100 can be used with smart slave devices, e.g. smart valves 102 with itsown serial controller 104 and transmitting and receiving circuit 106 asshown in FIG. 15. These other purposes for example can be counting thenumber of actuations or having other communication signals emanatingfrom the individual valve units and sent through the serialcommunication line 100 to be received to a processor or othercommunication device, e.g. communication module 15, at the end of theline, programming or parameterization functionality.

In an alternative embodiment, in order to transmit data from the drivermaster 108 to the slave (valve) on the same connecting trace 100 that isalso used to power the electronic circuitry and micro controller 104,the master device 108 modulates the current to create voltage pulsesthat are greater than the bias potential allowing the slave device toidentify that the data is coming from the master driver. The slave canonly respond to a master's request or command, it cannot initiatecommunication. When responding to a master's request, the slavemodulates the current to the single wire trace 100 in order to createvoltage pulses that are less than the bias potential, allowing themaster to identify that data is coming back from the slave.

This handshaking routine is comprised of data frames which consist of astart bit, 8 data bits and one stop bit. The complete data frameconsists of 8 bytes, an address byte, a command byte, five data bytesand one checksum byte. The checksum byte is simply the sum of thepreceding seven bytes and is used for error detection.

Circuitry 106 and 104 on the slave valve is able to decode these datapulses for parameter and/or diagnostic functions.

Addressing the slaves is required since the single wire communicationtrace is connected to the entire set of 32 valves. Thus, it is importantto identify which slave valve is being addressed. This addressingfunction for each smart valve is done on initial power-up, or isinitiated by the user when appropriate, and is achieved by theutilization of the existing “coil output” signals which are typicallyused to energize solenoid coils of conventional valves.

Upon power-up, the “coil output” signals are configured to sequentiallystrobe each coil trace 110 and 112 with a very fast pulse from coildriver 115, which is too fast to energize the coil 116, 118 of anattached valve 102. The common voltage is along line 113. A detectcircuit 114 in the slave is then triggered by the strobe pulse to allowthat specific slave to receive an address.

Once the first slave obtains an address from the master, the strobingsequence is incremented so the next slave can be assigned sequentialaddresses. The system continues this addressing routine until all 32possible slaves are assigned a sequential address. After all slaves areaddressed, the master can communicate to each individual slave withoutaffecting any other slave's function. Because each of the slavesreceives a sequential address (1-32), the smart driver can thencommunicate with each slave individually at any time during operation.Smart slaves may be mixed on the same manifold with regular (Non-smart)valves.

Each of the smart valves (slaves) connected to the one wire is able tocommunicate with the smart driver through its transmit and receivecircuit 120. Commands and data are sent from the smart driver to thesmart slaves along line 100. Data and slave type is sent from the smartslaves to the smart driver along line 100.

One function that the smart valve may have is counting the number ortimes it has been energized. The smart valves will detect the activationof both the “A” and “B” coils 116, 118 and will record the total countsinto non-volatile memory located on the smart valve circuitry.Additional slave types such as “smart pressure transducer” (Detect andreport air pressure) or “smart pressure regulator” (regulate airpressures) are also possible.

In this fashion, communication through the valve manifold block assemblyof a fluid control system is achieved by using a single serialcommunication line that is in direct contact with individual valve unitsthroughout the manifold block assembly.

In another embodiment shown in FIG. 16, a first series 130 of circuitboards 30, each circuit board being in a respective manifold block 12,is operably connected to a first driver 132 installed in communicationmodule 15. Each circuit board 30 shown in FIG. 16 in each manifold block12 is operably connected to a respective valve unit 13 as describedbefore. Each circuit board 30 has a control line segment 134 thatsimilarly extends from edge to edge in similar fashion to detection line96 as previously described by not being decremented but passing straightthrough from one edge to the other without dropping any positions. Thesegments 134 are joined together to form a control line 136 that extendsfrom the main communication module 15 to a second driver unit 138 in asecond communication module 140. The second driver unit 138 is thenconnected in similar fashion to a second series 142 of circuit boards32.

The control line 136 by being connected to a second communication module140 with its own driver 138 allows the fluid control system 10 to belonger and with more valve stations than what the original designcapacity of either driver 132 or the first series 130 of circuit boards13 dictated. Furthermore, the control line may provide a control signalto the second driver unit 138 that proportionally controls the inputvoltage to a valve unit 13. In this fashion, one of the valve units 13connected to the second series 142 of circuit boards may be aproportioning valve (indicated at 144) or other voltage dependent valvethat is actuated through respective circuit board 13 with variablevoltage. For example, the control input voltage may vary between 0-10volts to provide adjustable output pressure between 0-100 PSI. Whileonly one proportioning valve 144 is shown in FIG. 16, for simplicity ofthe drawings, the other valve units 13 in the second series 142 mayincorporate a plurality of proportioning valves 144.

Other variations and modifications are possible without departing fromthe scope and spirit of the present invention as defined by the appendedclaims.

The embodiments in which an exclusive property or privilege is claimedare defined as follows:
 1. A fluid control system comprising: a driverdevice and plurality of slave devices connected to said driver devicethrough an operating circuit for operating; a detection circuitconnected to each slave device to detect whether said operating circuitis active; said respective detection circuit connected to a singleserial communication line that is in communication with said driver forcommunicating information between said driver and said plurality ofslave devices; a fluid valve manifold having a plurality of valvemanifold blocks fastened to each other so as to form fluid pathwaysextending through said fluid valve manifold and a passage through eachvalve manifold block that aligns with each other to collectively form acontinuous electrical conduit receiving a series of connected circuitboards that each actuate a valve unit mounted to each valve manifoldblock; each circuit board having a set of conductive valve linesconnected to and extending between a respective set of first electricalconnectors and a respective set of second mating electrical connectors;a conductive common line in each circuit board connected to one voltageside of a respective first electrical connector and a respective secondmating electrical connector for connection to a respective conductivecommon line in another valve manifold block; and said single serialcommunication line is formed by said series of connected circuit boardswith each circuit board having a line segment with a respective firstelectrical connector and electrically connected to a respective secondmating electrical connector for connection to a respective firstelectrical connector in another circuit board.
 2. A fluid control systemas defined in claim 1 further comprising: at least one of said slavedevices having its respective detection circuit connect to said singleserial communication line through a microcontroller and a transmitterand receiving circuit in said at least one of said slave devices.
 3. Afluid control system as defined in claim 2 further comprising: saidsingle serial communication line communicating between said driver andsaid plurality of slave devices by dropping voltage pulses forcommunication from one of said drivers and to the other of said driverand said slave device and by raising voltage pulses for communicatingfrom the other of said driver and said slave device to one of saiddriver and slave devices.
 4. A fluid control system comprising: a fluidvalve manifold having a plurality of valve manifold blocks fastened toeach other so as to form fluid pathways extending through said fluidvalve manifold and a passage through each fluid valve manifold thataligns with each other to collectively form a continuous electricalconduit for receiving a first series of connected circuit boards thateach actuate a respective valve unit mounted to each valve manifoldblock; each circuit board having a set of conductive valve linesconnected to and extending between a respective set of first electricalconnectors at a first edge thereof and a respective set of second matingelectrical connectors at a second edge thereof opposite from said firstedge; a first communication module having a valve driver with aplurality of outputs for actuating the respective valve units connectedto said first series of connected circuit boards; a conductive commonline connected to one voltage side of a respective first electricalconnector and respective second mating electrical connector forconnection to a respective conductive common line in another valvemanifold block; a serial control line extending through the first seriesof connected circuit boards and connected to a second driver foractuating a second series of connected circuit boards; and said serialcontrol line is formed by said first series of connected circuit boardswith each circuit board having a line segment having respective firstelectrical connector at said first edge and a respective second matingelectrical connector at said second edge for connection to a respectivefirst electrical connector of another line segment in another circuitboard valve in another manifold block; said serial control lineconstructed to control the voltage for at least one of the plurality ofoutputs of the second driver to control the voltage to at least onevalve unit connected to the second series of connected circuit boards.5. A fluid control system as defined in claim 4 further comprising: atleast one valve connected to one of the circuit boards in the secondseries of connected circuit boards being a proportional valve.
 6. Afluid control system as defined in claim 5 further comprising: aplurality of valves connected to the second series of connected circuitboards being proportional valves.